Fluid control system for railroad rail sanding devices



Feb. 16, 1954 L, w, HAR S 2,669,472

FLUID CONTROL SYSTEM FOR RAILROAD RAIL SANDING DEVICES,

Filed Aug. 20, 1951 AL Lsnventor Patented Feb. 16, 1954 FLUID CONTROL SYSTEM FOR RAILROAD RAIL SANDING DEVICES Lewis W. Harms, Denver, Colo. Application August 20, 1951, Serial No. 242,687

4 Claims.

This invention relates to fluid control systems.

One of the objects of the invention is to provide a fluid control system for selectively supplying alternative fluid receiving instrumentalities from alternative sources of fluid supply.

Another object is to apply the invention to a sanding system for locomotives.

Other objects, advantages, and salient features will become more apparent from the description to follow, the appended claims, and the accompanying drawing in which:

Figure 1 is a diagrammatic side elevation of an articulated locomotive;

Figure 2 is a diagrammatic view of the piping system employed in Figure 1;

Figure 3 is an enlarged central section of Figure 2, portions being shown in section; and

Figure 4 is a view similar to Figure 3 showing an alternative form of the invention.

Referring in detail to the drawing, and parties-- larly Figure 1, an articulated locomotive is diagrammatically illustrated, this comprising fore and aft engine units Ni, ii and an intermediate engine unit I2. It is common practice to couple the fore and aft units, hereinafter referred to .3

as cab or control units, in reversed relationship, as shown, and to couple the intermediate unit in either of reversible end-for-end relationships. Since the intermediate unit may be reversibly coupled, it is common practice to provide it with sand boxes I3, I to which deliver sand ahead of one set of wheels and behind the other set, as shown by arrow I4 and double head arrow, Ida. It is apparent, therefore, that regardless of the direction of movement of the intermediate unit,

one set of wheels will receive sand ahead of same where the sand will effect optimum braking or traction between the wheels and tracks and that sand delivered behind the other set is substantially wasted.

Unit I0 is provided with sand boxes I5, I5a which deliver sand ahead of both sets of wheels, as shown by arrows I6, Ilia, assuming that the articulated locomotive is moving in the direction of arrow I'I. Unit II is provided with similar sand boxes I 8, Ifla, but since it is reversely coupled, the sand is delivered behind its sets of wheels, as shown by double head arrows I9, Illa.

Assuming, again, that an articulated locomotive of the prior art is moving in the direction of arrow I'I, it will be apparent that sand will b delivered to all points indicated by both the single and double head arrows. It will also be apparent that the sand delivered at Ha, I So, and I9, will produce no traction effect on the respective adjacent sets of wheels since it is delivered behind same. Thus, approximately one-half of the sand delivered to the tracks and wheels is wasted. If the articulated locomotive is moving in the direction of arrow Ila, it will also be ap parent that sand delivered at I 4, IBa and I5 is wasted since this is behind the adjacent sets of wheels. In the present invention sand is delivered at points It, Ilia and I4 when the articulated locomotive is moving in the direction of arrow I? and to points I9, I9a and Ida when it is moving in the direction of double head arrow Ila, the means for which will now be described.

Referring to Figure 3, a valve 23 is interposed in air conduit 2 I, which extends between the ends of unit I2, this conduit being coupled at its ends by suitable conventional flexible hose couplings C to air conduit 22 on unit I0 and air conduit 23 on unit I I. Valve 20 comprises a cylinder 24 having a hollow slideable piston 25 therein which is adapted to selectively close ports 25, 21 which connect, respectively, to sand boxes I4, Ma. A check valve 28 is disposed in conduit 22 and a similar check valve 29 is disposed in conduit 23.

Assuming that the articulated locomotive is moving in the direction of arrow IT and it is desired to apply sand to the wheels, the operation is as followsi Valve 36 in control unit It is opened and air flows from a source of pressure supply 3| to conduit 22,,to sand boxes I5, I501, through check valve 28 to conduit 2|, moving piston 25 to the right closing port 21 and opening port 26, to sand box I4, and then to check valve 29, closing same and preventing flow of air to sand boxes I8, I8a.

If unit II is the control unit with the articulated locomotive moving in the direction of arrow Ila, air is supplied from pressure source 32, through valve 33, to conduit 23 and sand boxes I 8, I So, thence through check valve 29 to conduit 2|, moving piston 25 to the left closing port 26 and opening port 21, to sand box Ma, and to check valve 28 which closes, preventing flow to sand boxes I5, I5a communicating therewith.

In some units, such as unit I2, it may simplify the conduits to provide two automatic valves rather than one, as previously described. Referring to Figure 4, valve units I20, I20o are disposed in conduit 2 I, but in reversed relationship. If air is supplied to the left end of conduit EI, both pistons I25 move to the right, opening port I25 and closing port I21. Similarly, if air is supplied to the right end of pipe 2|, both pistons move to the left, opening port I21 and closing port I26.

It will be understood that pistons I25 or 25 may be of any suitable form to positively move automatically between ends of their cylinders upon application of difierential pressure to their ends. As will be apparent, both pistons have restricted openings between their ends to restrict the rateof fiow therethrough and during the movement the pressure on one end face of the piston will be greater than on the other to effect movement. Any suitable buffer means such as a spring, dashpot, or the like (not shown) may be employed to cushion the stopping of the pistons when pressure is suddenly applied to one end thereof.

While the drawing illustrates two cab units and an intermediate unit, it is to be understood that this is exemplary only and othercombinations of units may be employed. For example, two or more intermediate units may be employed withcab units at the ends thereof.

The various fluid receiving instrumentalities indicated specifically as sand boxes may be any sanding apparatus which is fluid operated. Since these devices vary greatly in detail and are wellknown in the art, detailed description has been omitted in the interests of clarity. As previously alluded to, the invention may be'employed with fluid supplies and fluid receiving instrumentalities other than the specific installation on an articulated locomotive. Many modifications will become apparent-to those skilled in the art and the specific illustrations are to be regarded as exemplary only, and not limited thereto except as required by the prior art and scope or" the appended claims.

Having described the invention what is claimed as new is:

1. In articulated wheel mounted locomotive comprising two cab units provided with a compressed air supply and a fluid actuated sanding devices positioned to apply sand ahead of the wheels of each unit when the units are moving in a normal forward directioh'and behind the wheels of-a rearward unit when the latter is coupled to the forward unit so that its cab end points in the opposite direction; the improvement comprising, an airline connecting the cab units,

, check valve means disposed in a fluid supply conduit for the sanding device on each cab unit arranged to automatically close when asanding device control valve on the other unit is opened, whereby sand is delivered ahead of only the wheels of the forwardcab unit, so that each cab unit can deliver sandahea'd of its own wheels only.

ill

2. In an articulated locomotive in accordance with claim 1 wherein at least one intermediate 10- comotive unit is coupled between the cab units, the intermediate unit being of the type having sanding devices positioned and arranged to normally deliver sand ahead of one set of wheels and behind another set of wheels, the further improvement comprising; automatic fluid actuated valve means operable in response to Opening of the sanding control valve of'the forward cab unit to disestablish fluid communication to the sandin'g device on the intermediate unit which would normally deliver sand behind a set of wheels of the intermediate unit, so that sand is delivered by the intermediate unit only ahead of its own wheels.

3. An articulated locomotive having a central power unit and a cab and control unit ateach end, said locomotive being arranged for travel in either direction, the cab unit at the forward end being the control unit, the cab' and'thepower unit having supporting wheels, sanding means for the locomotive comprising a compressed air supply on each cab unit, an air operated sanding device for each pair of cab wheels, a sanding'dev'ice for each air of drive wheels on the power unit, an air pipe extending the entire length of the locomotive, each cab having a valve for controlling the how of air from the air supply to the air'pipe, the air pipe having a check valve at therear of each cab unit which permits air to flow away from said unit but prevents the flow of air "towards the cab unit whereby the operator in a cab unit cannot control the sanding "mechanism in the other unit, the power unit having two sanding devices each positioned to deliver sand to that side of the wheels nearest its ends, and valve means in the air line, comprising a cylinder having'an outlet port near each end, and a movable piston for automatically closing one port and opening the other to direct the air to the sanding'device nearest the cab that serves as the operating unit, whereby the sanding device ontheforward .side of the wheels only will function.

4. A device in accordancewith claim '3 in which the piston has an air passage permitting air to flow from one end to the other.

LEWIS WVHARMS.

References Cited in the file of'this patent UNITED STATES PATENTS Number Name Date 1,490,179 Morrow Apr/15,1924 1.521399 White i Jan. 6, "1925 

